The best WooCommerce side cart plugin for most stores is Caddy. It is the only side cart built on the WordPress Interactivity API and WooCommerce Store API, which means instant reactive updates with zero jQuery dependency. The free version includes a shipping meter, product recommendations, and Save for Later. XootiX Side Cart is the best alternative for stores that need a built-in shipping calculator.
What Is a Side Cart Plugin?
A side cart (also called a sliding cart, cart drawer, mini cart, or floating cart) is a WooCommerce plugin that replaces the default cart page with a slide-out panel. When a customer adds a product, the cart slides in from the right side of the screen. Customers can view items, change quantities, apply coupons, and proceed to checkout without leaving the product page.
The default WooCommerce cart is a standalone page. Every time a customer wants to check their cart, they navigate away from whatever they were browsing. This page-to-page transition is the single biggest friction point in the WooCommerce shopping flow.
Side cart plugins eliminate that friction. The cart stays accessible on every page. Shopping and cart management happen simultaneously.
Why Side Carts Reduce Cart Abandonment
WooCommerce stores lose an average of 70% of carts before checkout. The Baymard Institute has tracked this number across 49 studies, and it has stayed between 69-71% for over a decade.
The top 3 reasons customers abandon carts:
- Extra costs revealed too late (48%) – Side carts with shipping meters show cost thresholds upfront
- Required to create an account (26%) – Not a side cart issue, but side carts keep customers in the flow
- Checkout process too long/complicated (22%) – Side carts remove the cart-page step entirely
A side cart directly addresses reasons #1 and #3. When the cart is always visible with a shipping progress bar, customers see costs in real time. When checkout is one click from the side cart, the path from product to purchase shortens.
Stores that add a side cart with a free shipping meter report AOV increases of 15-25%, because customers can see exactly how much more they need to spend to hit the threshold.
The 7 Best WooCommerce Side Cart Plugins
1. Caddy
Best for: Stores that want the most modern architecture and a generous free version
Caddy is the only WooCommerce side cart built on the WordPress Interactivity API and WooCommerce Store API. This matters because it means zero jQuery dependency, reactive state management (the cart updates instantly without AJAX round-trips for UI changes), and alignment with where WordPress core development is heading.
The free version includes features that most competitors lock behind paywalls: a free shipping progress meter, in-cart product recommendations (manual, cross-sells, or upsells), Save for Later, a coupon field, and a cart bubble with live item count.
Caddy Pro adds a multi-tier Rewards Meter (stack free shipping, free gifts, and cart discounts across multiple thresholds), workflow automation (conditional popups, auto-applied coupons based on cart contents), a cart analytics dashboard, abandoned cart tracking, and an announcement bar with dynamic personalization variables.
Pricing: Free on WordPress.org. Pro: $99/year (1 site), $199/year (5 sites), $399/year (unlimited).
Active installs: 4,000+
Architecture: WordPress Interactivity API + WooCommerce Store API. ESM JavaScript, no jQuery.
Strengths:
- Only side cart on WordPress Interactivity API (modern, reactive, no jQuery)
- Generous free version (shipping meter, recommendations, Save for Later all included)
- Multi-tier Rewards Meter in Pro (not just a shipping bar)
- Standalone product (no ecosystem lock-in)
- HPOS compatible, block theme compatible
Limitations:
- No built-in shipping calculator (XootiX has this)
- Smaller install base than XootiX
- No express checkout integration (CartPops has this)
- Analytics dashboard is Pro-only
2. XootiX Side Cart WooCommerce
Best for: Stores that want the most proven option with the largest user base
XootiX is the market leader by install count with 80,000+ active installs and a 4.9-star rating across 447 reviews. It has been around for years and works with nearly any WooCommerce configuration.
XootiX offers three cart display styles (side cart, popup cart, and a regular cart widget), a built-in shipping calculator inside the cart, and Save for Later. The Pro version adds a rewards bar, product recommendations, checkout inside the cart, and custom cart icons.
Pricing: Free on WordPress.org. Pro: ~$99/year.
Active installs: 80,000+
Architecture: Traditional AJAX (admin-ajax.php), jQuery-dependent.
Strengths:
- Massive install base and review count (social proof)
- Built-in shipping calculator (unique among competitors)
- Three cart display styles
- Save for Later included in free version
- Mature, battle-tested codebase
Limitations:
- jQuery dependency (heavier, can conflict with modern themes)
- Reported theme conflicts with GeneratePress and some block themes
- Stock validation bugs reported in reviews
- Multi-currency issues noted
- Traditional AJAX architecture (not reactive)
3. FunnelKit Cart
Best for: Stores already using the FunnelKit suite (funnels, checkout, automations)
FunnelKit Cart is part of the FunnelKit ecosystem. The free version offers a solid side cart with a shipping bar, upsells, and coupon field. The Pro version adds milestone rewards (similar to Caddy’s Rewards Meter), A/B testing, and conditional upsells based on cart contents.
FunnelKit’s biggest advantage is its upsell engine. If you already use FunnelKit for checkout and funnel pages, the cart integrates with those upsell flows.
The drawback: you cannot buy FunnelKit Cart Pro standalone. It requires the FunnelKit Pro suite, which ranges from $99-$399/year. If you only want a side cart, that is an expensive path.
Pricing: Free version on WordPress.org. Pro requires FunnelKit suite ($99-$399/year).
Active installs: 20,000+
Architecture: Traditional AJAX, jQuery.
Strengths:
- Strong upsell and recommendation engine
- Milestone rewards in Pro
- Backed by a well-funded company
- Integrates with FunnelKit checkout and funnel builder
Limitations:
- Pro requires buying the full FunnelKit suite (no standalone cart purchase)
- Ecosystem lock-in (7+ screens to cancel subscription)
- jQuery dependency
- Free version is limited compared to Caddy’s free version
4. Modern Cart (by CartFlows / Brainstorm Force)
Best for: Stores using Astra theme or CartFlows who want a simple, clean cart drawer
Modern Cart is a newer entry backed by the Brainstorm Force team (the creators of Astra, the most popular WordPress theme). It offers a cart drawer and popup mode, a free shipping bar that auto-reads your WooCommerce shipping settings, and product recommendations.
The Astra team has massive resources and distribution. This plugin will keep growing. The price is competitive at $69-$79/year for 10 sites.
Pricing: Free version on WordPress.org. Pro: $69-$79/year (10 sites).
Active installs: Newer plugin, growing.
Architecture: Traditional AJAX, jQuery.
Strengths:
- Backed by the Astra team (large resources, active development)
- Competitive pricing ($69-$79/year for 10 sites)
- Auto-reads WooCommerce shipping settings for the shipping bar
- Clean, modern UI
Limitations:
- Newer plugin with a smaller community
- Less feature depth than Caddy or XootiX
- jQuery dependency
- Tight coupling with CartFlows ecosystem
5. Addonify Floating Cart
Best for: Budget-conscious stores that need a basic free side cart
Addonify is 100% free with no premium tier. It provides a functional floating cart with a shipping calculator, multiple trigger options, and GDPR compliance settings. If you need a basic cart drawer and do not want to pay for anything, Addonify is a solid choice.
The trade-off: no upsells, no product recommendations, no rewards meter, no analytics. It shows your cart. It does not help you grow your cart.
Pricing: Free (no premium version).
Active installs: 10,000+
Architecture: Traditional AJAX, jQuery.
Strengths:
- 100% free, no premium upsell
- Shipping calculator included
- Multiple trigger options (button click, add-to-cart, hover)
- GDPR compliant
Limitations:
- No product recommendations or upsells
- No rewards/shipping meter with thresholds
- No analytics or abandoned cart tracking
- No premium support
- jQuery dependency
6. CartPops
Best for: Developers who want hooks, filters, and API access in their side cart
CartPops is a developer-friendly side cart with a strong PHP hooks and JavaScript events API. It includes express checkout integration (Apple Pay, Google Pay via Stripe), a shipping meter, and product recommendations.
CartPops appeals to agencies and developers who build custom WooCommerce stores and need a side cart they can extend programmatically.
Pricing: Free on WordPress.org. Pro: ~$89/year.
Active installs: 4,000+
Architecture: Traditional AJAX, jQuery.
Strengths:
- Strong developer API (PHP hooks, JS events)
- Express checkout integration (Apple Pay, Google Pay)
- Shipping meter included
- Good for custom development projects
Limitations:
- Similar install count to Caddy (less social proof than XootiX)
- Minimal marketing presence
- jQuery dependency
- Less differentiated feature set
7. Fast Cart by Barn2
Best for: Stores that want a polished premium-only experience with strong documentation
Fast Cart by Barn2 is a premium-only plugin (no free version). It offers a clean side cart with product recommendations, quantity controls, a coupon field, and a shipping calculator. Barn2 is known for high-quality documentation and support.
The premium-only model means you cannot test before buying (though they offer a 30-day refund guarantee). Pricing is higher than most alternatives.
Pricing: From $79/year (1 site). No free version.
Active installs: Not publicly disclosed (premium only).
Architecture: Traditional AJAX, jQuery.
Strengths:
- Polished UI and user experience
- Strong documentation and support (Barn2 reputation)
- Shipping calculator included
- 30-day refund guarantee
Limitations:
- No free version (cannot test without buying)
- Higher price point
- jQuery dependency
- No rewards meter or multi-tier shipping incentives
- No abandoned cart tracking
Feature Comparison Table
| Feature | Caddy | XootiX | FunnelKit | Modern Cart | Addonify | CartPops | Fast Cart |
|---|---|---|---|---|---|---|---|
| Free shipping meter | Free | Free | Free | Free | Free | Free | Pro |
| Product recommendations | Free | Pro | Free | Pro | No | Pro | Pro |
| Save for Later | Free | Free | No | No | No | No | No |
| Coupon field in cart | Free | Free | Free | Free | No | Free | Pro |
| Rewards meter (multi-tier) | Pro | Pro | Pro | No | No | No | No |
| Shipping calculator | No | Free | No | No | Free | No | Pro |
| Abandoned cart tracking | Pro | No | Pro | No | No | No | No |
| Cart analytics | Pro | No | No | No | No | No | No |
| Workflow automation | Pro | No | Pro | No | No | No | No |
| Express checkout | No | No | No | No | No | Pro | No |
| Developer API (hooks) | Yes | Limited | Yes | Limited | Limited | Yes | Limited |
| Free version available | Yes | Yes | Yes | Yes | Yes (only) | Yes | No |
Architecture Comparison: jQuery/AJAX vs Interactivity API
This is the most important technical differentiator in the side cart plugin market right now.
Traditional Architecture (XootiX, FunnelKit, Modern Cart, Addonify, CartPops, Fast Cart)
Every side cart plugin listed above (except Caddy) uses the same basic approach:
- Load jQuery as a dependency
- Listen for add-to-cart clicks with jQuery event handlers
- Send an AJAX request to admin-ajax.php (or a custom REST endpoint)
- Wait for the server response
- Manually update the DOM (replace cart HTML, recalculate totals)
This works. It has worked for 10+ years. But it has three downsides:
- jQuery overhead. jQuery adds ~87KB (minified) to your page. Modern WordPress is moving away from jQuery, but these plugins still require it.
- Visible lag. The AJAX round-trip (step 3-4) takes 200-800ms. Customers see the delay between clicking “Add to Cart” and the cart updating.
- Manual DOM manipulation. When the server responds, the plugin has to figure out what changed and update the right page elements. This is fragile and can break when themes or other plugins modify the DOM.
Modern Architecture (Caddy)
Caddy 3.0 uses the WordPress Interactivity API, which works differently:
- Cart state is managed client-side as a reactive store
- When a customer adds a product, the UI updates optimistically (instantly)
- The Store API request happens in the background
- If the server confirms, nothing visible changes (the UI already updated)
- If the server rejects (out of stock), the UI rolls back
The result: the cart feels instant. There is no visible lag. And because the Interactivity API handles reactive rendering, Caddy does not manually manipulate the DOM. Only the elements that changed re-render.
Why this matters for store owners:
- Faster perceived performance (customers see instant updates)
- No jQuery loaded on pages where it is not needed
- Fewer conflicts with modern block themes that do not use jQuery
- Aligned with WordPress core direction (future compatibility)
Why this matters for developers:
- Clean, predictable state management
- No jQuery spaghetti code to debug
- Uses the same patterns as the block editor and WooCommerce block checkout
- Easier to extend without breaking
Should Architecture Influence Your Choice?
If your store runs a classic theme with jQuery already loaded, the architecture difference is less noticeable. The cart will work with any plugin on this list.
If you run a block theme, care about frontend performance, or want to minimize jQuery dependency, Caddy’s architecture is a measurable advantage. It is the only side cart plugin that does not add jQuery to your pages.
Pricing Comparison
| Plugin | Free | 1 Site | 5 Sites | 10 Sites | Unlimited |
|---|---|---|---|---|---|
| Caddy | Yes | $99/yr | $199/yr | – | $399/yr |
| XootiX | Yes | ~$99/yr | – | – | – |
| FunnelKit | Yes | $99/yr (suite) | – | – | $399/yr (suite) |
| Modern Cart | Yes | – | – | $69-79/yr | – |
| Addonify | Yes (only) | – | – | – | – |
| CartPops | Yes | ~$89/yr | – | – | – |
| Fast Cart | No | $79/yr | – | – | $249/yr |
Note: FunnelKit pricing requires buying the full FunnelKit suite. You cannot buy the cart plugin alone at Pro level.
Which Side Cart Plugin Should You Choose?
Choose Caddy if:
- You want the most modern architecture (Interactivity API, no jQuery)
- You want a generous free version with shipping meter, recommendations, and Save for Later
- You want multi-tier rewards (not just a free shipping bar)
- You want cart analytics and abandoned cart tracking
- You want a standalone product without ecosystem lock-in
Choose XootiX if:
- You need a built-in shipping calculator inside the cart
- You want the most battle-tested option (80K installs, 447 reviews)
- You need multiple cart display styles (side, popup, widget)
- You prioritize proven reliability over modern architecture
Choose FunnelKit if:
- You already use FunnelKit for checkout and funnels
- You want the strongest upsell engine
- You do not mind buying the full suite
Choose Modern Cart if:
- You use Astra theme and CartFlows
- You want a simple, clean cart at a lower price point
- You need multi-site licensing at $69-79/year
Choose Addonify if:
- You need a 100% free side cart with no premium upsell
- You want a basic floating cart and nothing more
- Budget is the primary constraint
Choose CartPops if:
- You are a developer building custom WooCommerce stores
- You need PHP hooks and JS events for extensibility
- You want express checkout (Apple Pay, Google Pay)
Choose Fast Cart if:
- You want premium-grade documentation and support
- You do not mind paying without trying a free version first
- You need a shipping calculator inside the cart
Frequently Asked Questions
What is the best free WooCommerce side cart plugin?
Caddy offers the most feature-complete free version among WooCommerce side cart plugins. The free version includes a sticky side cart with a free shipping progress meter, in-cart product recommendations (manual, cross-sells, or upsells), Save for Later, a coupon field, and a cart bubble with live item count. Addonify is the only 100% free alternative (no premium tier), but it lacks recommendations and rewards features.
Do side cart plugins slow down WooCommerce?
Most side cart plugins add 50-150KB of JavaScript (including jQuery) to your pages. Caddy is lighter because it does not load jQuery. It uses ESM JavaScript modules that only initialize when the cart block is present. On cached pages, the performance impact is minimal for any well-built side cart plugin. Test with Google PageSpeed Insights before and after installation to measure the actual impact on your specific store.
Can I use a side cart plugin with WooCommerce Subscriptions?
Caddy, XootiX, and FunnelKit all support WooCommerce Subscriptions. Caddy also supports Product Bundles and the All Products for Subscriptions extension. Check individual plugin documentation for the specific subscription features you need (subscription switching, renewal management in cart, etc.). If you sell subscriptions, the cart is only the front door: pair it with a subscription retention plugin to recover failed payments and reduce churn after the sale.
Will a side cart plugin conflict with my checkout plugin?
Side cart plugins operate on product and shop pages. They hand off to whatever checkout solution you use (default WooCommerce, FunnelKit Checkout, CartFlows, Stripe Checkout). Conflicts are rare but can happen with plugins that modify the add-to-cart process. Caddy uses the WooCommerce Store API for cart operations, which reduces conflict potential because it uses the same API as the WooCommerce block checkout.
What is the difference between a side cart, mini cart, floating cart, and cart drawer?
These are all names for the same interface pattern: a cart panel that slides in from the edge of the screen without loading a new page. “Side cart” and “sliding cart” are the most common terms. “Mini cart” refers to the compact format. “Floating cart” emphasizes that it hovers over page content. “Cart drawer” describes the slide-in animation. Every plugin in this comparison provides this same basic interface, with differences in features and implementation.
How do side cart plugins increase average order value?
Side carts increase AOV through three mechanisms: (1) Free shipping meters show customers how much more they need to spend, creating a natural incentive to add items. Stores report 15-25% AOV lifts from shipping thresholds. (2) In-cart product recommendations display cross-sells and upsells at the moment of highest purchase intent. (3) Multi-tier rewards meters (Caddy Pro, XootiX Pro, FunnelKit Pro) stack incentives across multiple spend levels. The cart is one lever. If you want gains across the whole funnel, that is the work of WooCommerce conversion optimization.
Should I use a free or premium side cart plugin?
Start with a free version. Caddy’s free version covers the core use case: a reactive side cart with a shipping meter, recommendations, Save for Later, and a coupon field. Upgrade to Pro when you need multi-tier rewards, cart analytics, abandoned cart tracking, or workflow automation. The free version alone will reduce cart abandonment and increase AOV for most stores.
Is WooCommerce Interactivity API better than AJAX for side carts?
The WordPress Interactivity API provides faster perceived performance through optimistic UI updates (the cart updates instantly, before the server responds). It eliminates jQuery dependency, reduces JavaScript payload size, and uses reactive state management instead of manual DOM manipulation. For customers, the difference is a cart that feels instant versus one with a brief loading delay. Caddy is currently the only WooCommerce side cart built on this API.
How do I migrate from one side cart plugin to another?
Side cart plugins do not store persistent data that needs migration (unlike SEO or form plugins). Deactivate your current side cart plugin, install and activate the new one, and configure your settings. The only consideration: if you use the plugin’s analytics or abandoned cart data, export that data before switching. Caddy and most alternatives activate with working defaults immediately after installation.
Do side cart plugins work with WooCommerce block themes?
Caddy is fully compatible with block themes because it registers as a WordPress block and does not depend on jQuery. XootiX and some other plugins report occasional conflicts with block themes because their jQuery-based scripts do not always load correctly in block theme contexts. If you run a block theme (like Twenty Twenty-Five, Flavor, or Flavor Pro), test the side cart after installation to confirm it opens and renders correctly.